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Scaling of undercut and bulge on solidified surface
No full textUndercut, which is the depression region near the fusion zone edge parallel to scanning direction on a solidified surface. Undercuts widely encountered in various welding, additive manufacturing, polishing technologies etc. decrease static, fatigue and fracture strength and increases stress concentration of solidified region. In this work, the domain for scaling includes the undercut and bulge of free surface on transverse cross-section. Utilizing previous scaling law accounting for Young-Laplace and Bernoulli equations for rippling and humping, the depth and width of undercut and height and width of bulge can be successfully scaled to be functions of dimensionless beam power, Marangoni, Peclet and Prandtl numbers, loss coefficient, surface active solute concentration, ratios of surface tension coefficients between undercut and bulge region, ratio between differences in melting and ambient temperatures and critical and melting temperatures, solid-to-liquid thermal conductivity ratio, etc. This work also utilized COMSOL Multiphsysics 5.6 to compute surface deformation affected by unsteady two-dimensional fluid flow and heat transfer. The scaled results are compared well with numerical computation or available experimental data. The effects of laser welding process parameters on surface deformation of undercut and bulge was studied as well
Study on Using Extended Manifold for Efficient Antenna Calibration
No full textWith the rapid development of the Internet of Things (IoT), there has been an increasing demand for positioning. Accurate angle estimation plays a vital role in providing positioning services. When estimating the angle of arrival (AoA), the array manifold is commonly utilized. However, this mathematical model only accounts for the phase difference between antennas and does not consider factors such as antenna polarization and coupling. To address the inaccuracies of the mathematical model, measurement methods are commonly employed to improve accuracy. This approach is known as antenna calibration. However, antenna calibration is time-consuming. Therefore, this thesis introduces an alternative mathematical model called the extended manifold. This model divides an antenna into multiple short dipoles to capture the antenna's characteristics, allowing for enhanced estimation accuracy and reduced time required for antenna calibration.
Typically, patch antennas are used for mobile phone positioning. However, these antennas often have irregularly shaped ground planes and contain multiple electronic components. These factors pose challenges for applying the traditional extended manifold method. To overcome these issues, this thesis proposes the application of image theory from electromagnetic theory to the extended manifold. In addition to utilizing simulation methods, this study also conducted measurements to verify the feasibility of the proposed method. The measured results demonstrate that the use of the extended manifold can indeed reduce the time required for antenna calibration. The angular spacing for both vertical and horizontal angles can be expanded to every 10 degrees, significantly saving time compared to the previous need for measurements at every angle. Furthermore, the results indicate that the extended manifold exhibits higher accuracy than traditional linear interpolation
Digitizing Budget Preparation for the Traditional Manufacturing Industry - A Case Study of Company
No full textUnder the development of liberalization and globalization economic competition, the traditional manufacturing industry has gradually been replaced by emerging high-tech industries and faced industrial transformation. Our country's traditional manufacturing industry should follow the trend, strengthen resource integration, and establish a highly efficient enterprise system. In the future, the traditional manufacturing industry should move towards technological innovation and modern management models, and through technology upgrades and perfect enterprise management, achieve sustainable operations. Budget management is a tool for enterprise management that determines resource allocation and helps achieve goal plans. There is a close relationship between budget and performance. Performance can be used to evaluate the actual effect of achieving enterprise goals. After the annual budget is completed, the company can use it as an important basis for controlling the budget and evaluating performance. From the perspective of sustainable management, budget management can help enterprise operators pre-plan future operations, digitize budget management, identify problems and integrate resource. This helps make concrete preparations in advance to make enterprises more competitive and make business decisions more data-driven. The purpose of enterprise budget management is to assist enterprises in effectively allocating and controlling resources to achieve their goals. Budget management can help enterprises determine the priority of resource allocation, improve financial control, reduce costs, improve operational efficiency, and promote business development. Through budget management, enterprises can establish long-term and short-term goals, carry out planning and evaluation, and adjust their business strategies in a timely manner to achieve better performance and long-term competitiveness.
This study will focus on planning and implementing annual business goals and action plans so that sales, production, finance, and management departments can follow and coordinate with each other. This provides effective ways to reduce the time and manpower required for budget preparation
Design of Relay-Feedback Modulator/Demodulator for Underwater Acoustic Telephone
No full textThis thesis presents a design of an underwater acoustic telephone, which transmits and receives ultrasound waves carried with vocal signals in water, for communication between divers and submarines. The acoustic telephone mainly consists of a communication transducer, a transceiver, a modulator, a demodulator, a microphone, and a speaker. Speech signals are sent by modulating the frequency of sound waves. Both the frequency modulator and demodulator are designed specifically using relay-feedback oscillators and implemented on a Cyclone IV FPGA with a core clock of 100 MHz, with the carrier frequency of 26 kHz and the modulation bandwidth of about 8 kHz. The system is tested successfully with a communication distance of about 50 m
ESG: Trends in Green Chemical Management Development and Enhancing Corporate Chemical Management
No full textGreen chemical management is a topic that has received increasing attention in recent years. The harm caused by chemicals to the environment and human health has become a growing concern, and companies need to better manage and control their use of chemicals to reduce their impact on the environment and human health. This paper aims to explore the development trends of green chemical management and methods to improve the chemical management capabilities of companies. A case study of N company is conducted using SWOT analysis to develop strategies. The paper demonstrates how to effectively manage chemicals through digitalization, digital optimization, and digital transformation according to the strategy, and presents the results in the company's 2021 sustainability report.
This section introduces the basic concepts and objectives of green chemical management, and emphasizes its importance and necessity. It analyzes the development trends of green chemical management, including the establishment of international green chemical management regulations, ESG disclosure requirements for green chemical products, and other related aspects. The paper also presents existing green chemical management systems, relevant policies, and practical case studies to help businesses understand the specific practices and experiences of green chemical management.
This paper also proposes methods to improve the chemical management capabilities of businesses, including establishing an effective chemical management system and strengthening chemical safety training and management. The aim of this paper is to provide a comprehensive analysis of the development trends of green chemical management and methods for improving the chemical management capabilities of businesses to help them better address environmental and health issues and achieve sustainable development
A Study of the Performance of Agile Software Development Methodology- A Case Study of the Reporting System in an Electronic Ticketing Company
No full textProvision of traffic reports is a vital business service for electronic ticketing companies. However, the development of these reports involves frequent and substantial changes, making it challenging for the traditional stable waterfall software development method to respond quickly to evolving requirements and adjustments. Therefore, the case company aims to address the pain points associated with the frequent and significant rule changes in report generation by harnessing the benefits of Agile software development. By employing the incremental and iterative characteristics of Agile, the company seeks to enhance and accelerate the delivery of traffic reports with increased accuracy. This research focuses on conducting an in-depth investigation into the implementation of Agile software development in the report system of a specific electronic ticketing company. The study aims to explore the process and methodologies employed for introducing Agile software development, as well as its impacts on both advantages and disadvantages. Furthermore, the research delves into a practical development case study, analyzing the performance effects of the case company's report system following the adoption of Agile software development from five distinct research perspectives.
In this study, semi-structured individual in-depth interviews were conducted from different perspectives, including users and developers, as well as managers and frontline employees at various hierarchical levels within the electronic ticketing company. The aim was to understand the obstacles and challenges encountered during the development process of the report system. Additionally, the advantages and disadvantages of Agile software development were explored, and a comparison was made between the perspectives of the case company and relevant literature from national and international sources on these advantages and disadvantages. Finally, following the six measurement criteria proposed by Lin et al. (2015) for project performance evaluation, the researchers synthesized and organized five dimensions for evaluating project performance in this study. These dimensions included development timeline, development cost, information system quality, user satisfaction, and development team performance. Based on an actual report development case study, the study investigated the performance evaluation of the electronic ticketing company's report system after adopting Agile software development methods.
Based on the findings of this study, it was observed that the introduction of Agile software development methods in the report system of a specific electronic ticketing company encountered significant challenges and incurred higher costs during the initial implementation phase. However, considering the company's long-term development perspective, the adoption of Agile software development methods for the report system indeed yielded substantial benefits. Additionally, the study revealed that the advantages and disadvantages of Agile software development could be influenced by the company's culture. From the perspective of project performance evaluation, it was evident that Agile software development methods excelled in projects with frequent changes, facilitating smoother, more efficient, and flexible adaptations
Study of Nanocomposite of Spherical Tungsten Trioxide Nanorods and Nitrogen-doped Reduce Graphene Oxide for Acetone Gas Sensing Applications
No full textThis study investigates and prepares tungsten trioxide (WO3) nanostructures and nitrogen-doped reduced graphene oxide (rGO) by hydrothermal synthesis. Urea is used in both synthesis precursors. WO3 is synthesized with different amounts of urea to change the morphology of nanostructures. While N-doped rGO is reduced and doped with urea simultaneously. SEM, XRD, EDS, and other instruments analyze the physical properties of the material. Meanwhile, the relationship between the sensing performances and the structural change is explored by electrical analysis. It is confirmed that the sensing ability of the nanocomposites to acetone gas could be further improved.
In order to improve the responsivity to acetone gas, a p-n heterojunction is fabricated by depositing n-type WO3 on a p-type silicon substrate to form a gas sensor. According to the experimental results, the WO3 nanostructure synthesized with the precursor solution containing 2.5 g urea has the highest responsivity. After WO3 is combined with n-type N-doped rGO, the responsivity further increases to a higher value. The results indicate that the optimal working temperature of WO3 nanorods is 225 oC. Due to the assistance of the exposed (002) facets, the responsivity of pure WO3 to 100 ppm acetone gas reaches 66.63%. After it combines with N-doped rGO, the responsivity increases to 84.82%. The gas sensor of the nanocomposites has a response time of 22.2 s and a recovery time of 36.0 s. The WO3/N-doped rGO acetone gas sensor also has significant selectivity to various gas species
Study of Treatment Efficiencies for Adding Nitrogen and Phosphorus Wastewater To Polluted River Water by Integrated Vertical Flow Constructed Wetland and Integrated Horizontal Flow Constructed Wetland
No full textThis study conducted research using two test tanks, one featuring a composite vertical flow constructed wetland and the other with a composite horizontal flow constructed wetland. The hydraulic retention time of the two tanks was controlled, along with variations in high/low carbon sources, high/low nitrogen sources, and fixed phosphorus nutrient concentrations. The aim was to investigate the performance of the two types of composite constructed wetland tanks under different hydraulic retention times and concentrations of carbon and nitrogen sources.
The study is divided into two stages of experimentation: (1) with a hydraulic retention time (HRT) of 72 hours, and (2) with an HRT of 48 hours. The experiments investigate the removal efficiency of pollutants from the influent water under different water quality conditions. The experiments involve controlling the inflow water flow rate and employing varying combinations of high/low carbon sources, high/low nitrogen nutrients, and fixed phosphorus nutrient concentrations, while keeping the plant and tank filter materials constant.
Additionally, the study examines the treatment capacity of a composite vertical flow constructed wetland and a composite horizontal flow constructed wetland when exposed to polluted river water with added nitrogen and phosphorus wastewater. The experimental results show that the best removal efficiency for both composite vertical flow and composite horizontal flow wetlands is achieved with an HRT of 48 hours.
Regarding total phosphorus, the results show that in the first stage (HRT of 3 days), the average removal rate in the composite vertical flow tank is 61.9%, and in the composite horizontal flow tank, it is 57.7%. In the second stage (HRT of 2 days), the average removal rate in the composite vertical flow tank is 52.9%, and in the composite horizontal flow tank, it is 52.1%.
As for total nitrogen, the results indicate that in the first stage (HRT of 3 days), the average removal rate in the composite vertical flow tank is 50.6%, and in the composite horizontal flow tank, it is 70.8%. In the second stage (HRT of 2 days), the average removal rate in the composite vertical flow tank is 59.9%, and in the composite horizontal flow tank, it is 74.3%.
Taiwan Creative Content Agency and its role of entrepreneurial intermediary
No full textAs an intermediary organization, Taiwan Creative Content Agency (TAICCA) has a social responsibility to develop the cultural industries while considering the interests of various actors within the industry, including private sectors, companies, cultural content creators, and organizations. Establishing the TAICCA as an independent administrative institution aims to enhance the application of cultural content, create Taiwanese cultural content brands, integrate industry stakeholders, and create a healthy industrial environment. The TAICCA achieves its mission by facilitating investment and collaboration between companies and cultural content creators, transcending the traditional concept of arts and culture subsidies, and strengthening cooperation with international partners. This study analyzes the innovative practices of the TAICCA from the perspective of entrepreneurship in New Public Management. It applies the Business Model Canvas proposed by Osterwalder and Pigneur to examine how it delivers and creates value and its strategies for connecting domestic and international organizational networks.
Using a case study approach, this research addresses three research questions: Firstly, what are entrepreneurship and the innovative practices of the TAICCA? Who are the beneficiaries of its services? And how does it differ from or resemble previous government organizations? Secondly, as an intermediary, how does the TAICCA centrally coordinate government resources and private resources, and what activities and plans do it promote to construct the financial investment environment and industry chain of Taiwan's cultural content industry? Lastly, what challenges and difficulties have the TAICCA faced in self-funding (revenue and costs)?
The findings of this study are as follows: Firstly, the services provided by the TAICCA exhibit characteristics such as risk and cost reduction for cultural content creators, customization, and proximity. The TAICCA connects international markets with cultural content creators as an intermediary organization and communicating channel. Secondly, forming partnerships between the TAICCA and its collaborators is based on providing and exchanging resources, information, and experiences. Lastly, creating revenue sources requires a deeper evaluation of the market, target audience, industry, and innovative thinking
The Effects of Job Content Plateau on Proactive Career Behaviors: A Perspective from the Job Demands-Resources Model.
No full textAs public education advances, people expect more from their careers, including utilizing their strengths, diverse job content, and opportunities for learning and success. However, companies are restructuring and streamlining to stay competitive and improve efficiency, which can lead to career plateau and negative feelings for employees resulting from limited development and challenging work content. This study examines how job content plateau affects employees, using the stress theory of "job demands-resources model" to explore the relationship between emotional exhaustion, resilience, and proactive career behavior. Results from a survey of 265 financial services industry employees in Taiwan suggest that emotional exhaustion has a mediating effect, but resilience does not moderate the relationship. Finally, the practical implications of the research results are discussed, and suggestions for future research directions are proposed